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Register a new userSpin dynamics in helical molecules with non-linear interactions
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Added by
Francisco Dominguez-Adame
Publication date
2017
fields
Physics
and research's language is
English
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It is widely admitted that the helical conformation of certain chiral molecules may induce a sizable spin selectivity observed in experiments. Spin selectivity arises as a result of the interplay between a helicity-induced spin-orbit coupling and electric dipole fields in the molecule. From the theoretical point of view, different phenomena might affect the spin dynamics in helical molecules, such as quantum dephasing, dissipation and the role of metallic contacts. Previous studies neglected the local deformation of the molecule about the carrier thus far, but this assumption seems unrealistic to describe charge transport in molecular systems. We introduce an effective model describing the electron spin dynamics in a deformable helical molecule with weak spin-orbit coupling. We find that the electron-lattice interaction allows the formation of stable solitons such as bright solitons with well defined spin projection onto the molecule axis. We present a thorough study of these bright solitons and analyze their possible impact on the spin dynamics in deformable helical molecules.
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In this paper an effective integrable non-linear model describing the electron spin dynamics in a deformable helical molecule with weak spin-orbit coupling is presented. Non-linearity arises from the electron-lattice interaction and it enables the formation of a variety of stable solitons such as bright solitons, breathers and rogue waves, all of them presenting well defined spin projection onto the molecule axis. A thorough study of the soliton solutions is presented and discussed.
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